Cousin primes: Difference between revisions

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→‎{{header|Phix}}: added syntax colouring the hard way
(Add FOCAL)
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=={{header|Phix}}==
<!--<lang Phix>-->
<lang Phix>function has_cousin(integer p) return is_prime(p+4) end function
<span style="color: #008080;">function</span> <span style="color: #000000;">has_cousin</span><span style="color: #0000FF;">(</span><span style="color: #004080;">integer</span> <span style="color: #000000;">p</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">return</span> <span style="color: #7060A8;">is_prime</span><span style="color: #0000FF;">(</span><span style="color: #000000;">p</span><span style="color: #0000FF;">+</span><span style="color: #000000;">4</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">end</span> <span style="color: #008080;">function</span>
for n=2 to 7 do
<span style="color: #008080;">for</span> <span style="color: #000000;">n</span><span style="color: #0000FF;">=</span><span style="color: #000000;">2</span> <span style="color: #008080;">to</span> <span style="color: #000000;">7</span> <span style="color: #008080;">do</span>
integer tn = power(10,n)
<span style="color: #004080;">integer</span> <span style="color: #000000;">tn</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">power</span><span style="color: #0000FF;">(</span><span style="color: #000000;">10</span><span style="color: #0000FF;">,</span><span style="color: #000000;">n</span><span style="color: #0000FF;">)</span>
sequence res = filter(get_primes_le(tn-9),has_cousin)
<span style="color: #004080;">sequence</span> <span style="color: #000000;">res</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">filter</span><span style="color: #0000FF;">(</span><span style="color: #7060A8;">get_primes_le</span><span style="color: #0000FF;">(</span><span style="color: #000000;">tn</span><span style="color: #0000FF;">-</span><span style="color: #000000;">9</span><span style="color: #0000FF;">),</span><span style="color: #000000;">has_cousin</span><span style="color: #0000FF;">)</span>
res = columnize({res,sq_add(res,4)})
<span style="color: #000000;">res</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">columnize</span><span style="color: #0000FF;">({</span><span style="color: #000000;">res</span><span style="color: #0000FF;">,</span><span style="color: #7060A8;">sq_add</span><span style="color: #0000FF;">(</span><span style="color: #000000;">res</span><span style="color: #0000FF;">,</span><span style="color: #000000;">4</span><span style="color: #0000FF;">)})</span>
printf(1,"%,d cousin prime pairs less than %,d found: %v\n",{length(res),tn,shorten(res,"",min(4,5-floor(n/2)))})
<span style="color: #7060A8;">printf</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"%,d cousin prime pairs less than %,d found: %v\n"</span><span style="color: #0000FF;">,{</span><span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">res</span><span style="color: #0000FF;">),</span><span style="color: #000000;">tn</span><span style="color: #0000FF;">,</span><span style="color: #7060A8;">shorten</span><span style="color: #0000FF;">(</span><span style="color: #000000;">res</span><span style="color: #0000FF;">,</span><span style="color: #008000;">""</span><span style="color: #0000FF;">,</span><span style="color: #7060A8;">min</span><span style="color: #0000FF;">(</span><span style="color: #000000;">4</span><span style="color: #0000FF;">,</span><span style="color: #000000;">5</span><span style="color: #0000FF;">-</span><span style="color: #7060A8;">floor</span><span style="color: #0000FF;">(</span><span style="color: #000000;">n</span><span style="color: #0000FF;">/</span><span style="color: #000000;">2</span><span style="color: #0000FF;">)))})</span>
end for</lang>
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
<small>(Uses tn-9 instead of the more obvious tn-4 since none of 96,95,94,93,92 or similar could ever be prime. Note that {97,101} is deliberately excluded from < 100.)</small>
end for<!--</lang>-->
<small>(Uses tn-9 instead of the more obvious tn-4 since none of 96,95,94,93,92 or similar with 9..99999 prefix could ever be prime. Note that {97,101} is deliberately excluded from < 100.)</small>
{{out}}
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7,794

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